In the broadest terms, the research at the Population Studies Center focuses on 1) fertility and family planning, 2) population distribution and differentiation. Many of the research projects have policy implications, and increasing attention is being paid to this aspect of our work. Current study topics include research on residential and school racial segregation; agricultural development and fertility in rural areas; the relation of women's labor force participation and the value of women's time to fertility in developing countries; modeling the relationships between fertility expections and contraceptive failure rates to aggregate fertility levels; the role of breast-feeding on fertility, patterns of infant mortality, and population growth; measurement and implications of population clustering; the importance of community level variables on fertility; and the relation of fertility to marital stability.